Re^2: enumerating values for slopes

$ perl slope3.pl
Prototype mismatch: sub math1::pi () vs none at ../math1.pm line 13.
Constant subroutine pi redefined at ../math1.pm line 7.
Subroutine main::pi redefined at /usr/share/perl/5.18/Exporter.pm line
+ 66.
 at slope3.pl line 6.
Prototype mismatch: sub main::pi: none vs () at /usr/share/perl/5.18/E
+xporter.pm line 66.
 at slope3.pl line 6.
slopes are 0 5 8 11 14 30 90
runs are 2.25 3.25 4 5
An angle of 0 degrees, or 0 radians, and run of 2.25 has a rise of 0
An angle of 0 degrees, or 0 radians, and run of 3.25 has a rise of 0
An angle of 0 degrees, or 0 radians, and run of 4 has a rise of 0
An angle of 0 degrees, or 0 radians, and run of 5 has a rise of 0
An angle of 5 degrees, or 0.0872664625997165 radians, and run of 2.25 
+has a rise of 0.196849492933329
An angle of 5 degrees, or 0.0872664625997165 radians, and run of 3.25 
+has a rise of 0.284338156459253
An angle of 5 degrees, or 0.0872664625997165 radians, and run of 4 has
+ a rise of 0.349954654103696
An angle of 5 degrees, or 0.0872664625997165 radians, and run of 5 has
+ a rise of 0.43744331762962
An angle of 8 degrees, or 0.139626340159546 radians, and run of 2.25 h
+as a rise of 0.316216878080381
An angle of 8 degrees, or 0.139626340159546 radians, and run of 3.25 h
+as a rise of 0.456757712782772
An angle of 8 degrees, or 0.139626340159546 radians, and run of 4 has 
+a rise of 0.562163338809566
An angle of 8 degrees, or 0.139626340159546 radians, and run of 5 has 
+a rise of 0.702704173511957
An angle of 11 degrees, or 0.191986217719376 radians, and run of 2.25 
+has a rise of 0.437355695559867
An angle of 11 degrees, or 0.191986217719376 radians, and run of 3.25 
+has a rise of 0.631736004697585
An angle of 11 degrees, or 0.191986217719376 radians, and run of 4 has
+ a rise of 0.777521236550874
An angle of 11 degrees, or 0.191986217719376 radians, and run of 5 has
+ a rise of 0.971901545688592
An angle of 14 degrees, or 0.244346095279206 radians, and run of 2.25 
+has a rise of 0.560988006397157
An angle of 14 degrees, or 0.244346095279206 radians, and run of 3.25 
+has a rise of 0.810316009240337
An angle of 14 degrees, or 0.244346095279206 radians, and run of 4 has
+ a rise of 0.997312011372723
An angle of 14 degrees, or 0.244346095279206 radians, and run of 5 has
+ a rise of 1.2466400142159
An angle of 30 degrees, or 0.523598775598299 radians, and run of 2.25 
+has a rise of 1.29903810567666
An angle of 30 degrees, or 0.523598775598299 radians, and run of 3.25 
+has a rise of 1.87638837486628
An angle of 30 degrees, or 0.523598775598299 radians, and run of 4 has
+ a rise of 2.3094010767585
An angle of 30 degrees, or 0.523598775598299 radians, and run of 5 has
+ a rise of 2.88675134594813
An angle of 90 degrees, or 1.5707963267949 radians, and run of 2.25 ha
+s a rise of 3.67452885446896e+16
An angle of 90 degrees, or 1.5707963267949 radians, and run of 3.25 ha
+s a rise of 5.3076527897885e+16
An angle of 90 degrees, or 1.5707963267949 radians, and run of 4 has a
+ rise of 6.53249574127815e+16
An angle of 90 degrees, or 1.5707963267949 radians, and run of 5 has a
+ rise of 8.16561967659768e+16
pi is 3.14159265358979
$ cat slope3.pl
#!/usr/bin/perl -w
use strict;
use 5.010;
BEGIN { push @INC, ".."; }
use math1;
use Math::Trig;

my @slope = (0.0, 5.0, 8.0, 11.0, 14.0, 30.0, 90.0);
say "slopes are @slope";

my @run = (2.25, 3.25, 4, 5);
say "runs are @run";



foreach my $var1 (@slope) {
   my $s = degrees_to_radians($var1);
   foreach my $var2 (@run) {
   my $t = $var2 * tan($s);
     
  say "An angle of $var1 degrees, or $s radians, and run of $var2 has 
+a rise of $t";
 } 
 } 

my $a = pi();
say "pi is $a";
__END__ 
$
[download]

I made this as quick and dirty as I had to to get results. I like the results partially, in that I believe they're correct. The aspiration to have my own module was admirable for its valor, but not with its merits. I figured out that what I was doing came within spitting distance of *literally* re-inventing the circle.

$ cat math1.pm
package math1;
require Exporter;

our @ISA = qw(Exporter);
our @EXPORT = qw( pi degrees_to_radians);

sub pi{
use 5.010;
use Math::Trig ':pi';

my $a = pi;
return $a;
}

sub degrees_to_radians{
use 5.010;
use Math::Trig qw(deg2rad);

my $a = shift;
my $b = deg2rad($a);
return $b;
}

1;

$
[download]

I'm still fishing for people's experience with this, but I'll post a cleaned-up version of this that relies on cpan properly, instead of wrapping the calls and confusing perl.exe. Thanks all for comments.

Comment on Re^2: enumerating values for slopes Select or Download Code

Replies are listed 'Best First'.
Re^3: enumerating values for slopes by Laurent_R (Canon) on Sep 22, 2014 at 06:15 UTC
Although it probably does not have any consequences here, I would suggest that you avoid using the $a (and $b) variable, because $a and $b are special purpose global variables used for sorting data (and a few other specific uses).	[reply]
Re^4: enumerating values for slopes by Aldebaran (Curate) on Sep 23, 2014 at 05:04 UTC
`$ perl slope5.pl Can't use string ("4.3125") as an ARRAY ref while "strict refs" in use + at ../utils1.pm line 39. $ cat slope5.pl #!/usr/bin/perl -w use strict; use 5.010; use Math::Trig; BEGIN { push @INC, ".."; } use utils1; my @AoA; my $aoa_ref = \@AoA; my @vector = (4.3125, 0.4375); push @AoA, @vector; @vector = (4.375, 0.375); push @AoA, @vector; @vector = (4.4375, 0.375); print_aoa($aoa_ref); __END__ $` [download] Thought I would be comparing hypotenuses to heights but can't see why perl doesn't this is ok.	[reply] [d/l]
Re^5: enumerating values for slopes by Laurent_R (Canon) on Sep 23, 2014 at 17:36 UTC
The error occurs in the module, but the coding error is actually located in your calling program. When you do this: `my @vector = (4.3125, 0.4375); push @AoA, @vector; @vector = (4.375, 0.375); push @AoA, @vector;` [download] you are not creating an array of arrays (AoA), but a simple array whose 4 elements are: `(4.3125, 0.4375, 4.375, 0.375)` [download] You need to push on @AoA a reference to @vector: `my @vector = (4.3125, 0.4375); push @AoA, \@vector; @vector = (4.375, 0.375); push @AoA, \@vector;` [download] or build directly an array reference: `push @AoA, [4.3125, 0.4375]; push @AoA, [4.375, 0.375];` [download] I guess this should solve your issue. As I said earlier, you should avoid using the $a and $b variables, they are special variables used among other things for sorting, they behave differently from other variables, and using as you do them might lead to difficult-to-track bugs. You may use $c or $d, if you like, this will not be a problem, but I would personally put a more meaningful name helping comprehension of what they represent. Update: As pointed below by farang the first method above for building an AoA is actually buggy. Use the second one. Thanks to farang for picking that.	[reply] [d/l] [select]
Re^6: enumerating values for slopes by farang (Chaplain) on Sep 24, 2014 at 02:07 UTC
Re^7: enumerating values for slopes by Laurent_R (Canon) on Sep 24, 2014 at 06:59 UTC
Re^6: enumerating values for slopes by Aldebaran (Curate) on Sep 24, 2014 at 06:30 UTC
Re^5: enumerating values for slopes by Laurent_R (Canon) on Sep 23, 2014 at 06:11 UTC
Your error is in the `../utils1.pm` module, but you don't show the code for that module. Difficult to help you in such conditions.	[reply] [d/l]
Re^6: enumerating values for slopes by Aldebaran (Curate) on Sep 23, 2014 at 07:10 UTC
Re^5: enumerating values for slopes by Aldebaran (Curate) on Sep 23, 2014 at 06:40 UTC
What I found when field measuring was that it was much more attainable to get hypotenuses and heights, so that left me looking for arcsin. I had hoped to get this processed as an AoA, but I'm not quite there yet.... $ perl slope8.pl bath-left theta is 5.82263230478133 bath-middle theta is 4.91710033552881 bath-right theta is 4.84767847916148 dining-south theta is 15.2575232904564 john-north theta is 16.0133944239485 middle-front theta is 24.6243183521641 south-front theta is 14.4775121859299 $ cat slope8.pl #!/usr/bin/perl -w use strict; use 5.010; use Math::Trig; BEGIN { push @INC, ".."; } use utils1; my @AoA; my $aoa_ref = \@AoA; my $tja = 0.4375/4.3125; say "bath-left"; my $hja = asin $tja; my $degrees = rad2deg($hja); say "theta is $degrees"; $tja = 0.375/4.375; $hja = asin $tja; say "bath-middle"; $degrees = rad2deg($hja); say "theta is $degrees"; say "bath-right"; $tja = 0.375/4.4375; $hja = asin $tja; $degrees = rad2deg($hja); say "theta is $degrees"; say "dining-south"; $tja = 1.25/4.75; $hja = asin $tja; $degrees = rad2deg($hja); say "theta is $degrees"; say "john-north"; $tja = 1.0/3.625; $hja = asin $tja; $degrees = rad2deg($hja); say "theta is $degrees"; say "middle-front"; $tja = 1.875/4.5; $hja = asin $tja; $degrees = rad2deg($hja); say "theta is $degrees"; say "south-front"; $tja = 1.125/4.5; $hja = asin $tja; $degrees = rad2deg($hja); say "theta is $degrees"; __END__ $ [download]	[reply] [d/l]